Breanna Tyrell, Jenna Meltzer, Sarah Park, Garrett Scheliga

PROTEINS



1. Components
  • Chains of amino acids (polymers)
  • A typical protein has 200-300 amino acids.
  • Polypeptide chains
  • Antibodies- immune system-related proteins called immunoglobulins.
    • Consist of 4 polypeptides (2 heavy and 2 light chains)
    • This gives the antibody its ability for binding antigen.

2. Physical description
  • Four different structures of proteins.
    • Primary Structure- Amino acid chain (sequence)
    • Secondary Structure- Folding/coiling of chains (Alpha-helix & Beta-sheets)
    • Tertiary Structure- The folding of the polypeptide upon itself
    • Quaternary Structure- Two or more polypeptides joined together
  • Amino acid general structure -
external image 300px-AminoAcidball.png

2a. Job description
  • Help carry out activities and functions in the human body
  • A subclass of the functional proteins is the group of polypeptides referred to as enzymes which help carry out chemical reactions in the body
  • There are an estimated 100,000 different proteins that each serve a different function/purpose
  • Helps heal injuries and protects body from disease

3. Photo
external image Myoglobin.png
4. Where is molecule formed?
    • Proteins are synthesized in the Cytoplasm

5. Where is the molecule found in the cell?
  • Proteins are found throughout cells. Once they are made they are used for whatever they were needed.
    • For example, enzymes are used to catalyze reactions such as in the Electron Transport Chain.

6. How does the molecule work?

Antibodies - are specialized proteins involved in defending the body from antigens (foreign invaders). One way antibodies destroy antigens is by immobilizing them so that they can be destroyed by white blood cells.

Enzymes - are proteins that facilitate biochemical reactions. They are often referred to as catalysts because they speed up chemical reactions. Examples include the enzymes lactase and pepsin. Lactase breaks down the sugar lactose found in milk. Pepsin is a digestive enzyme that works in the stomach to break down proteins in food.

Transport Proteins - are carrier proteins which move molecules from one place to another around the body. Examples include hemoglobin and cytochromes. Hemoglobin transports oxygen through the blood. Cytochromes operate in the electron transport chain as electron carrier proteins.

BIBLIOGRAPHY

Carpi, Anthony. "Fats and Proteins." Visionlearning. N.p., n.d. Web. 14 Apr. 2011.
<http://www.visionlearning.com/library/module_viewer.php?mid=62>.

"Antibody Structure." The Biology Project. N.p., n.d. Web. 14 Apr. 2011. <http://www.biology.arizona.edu/immunology/tutorials/antibody/structure.html>.

__http://www.gbiosciences.com/EducationalUploads/EducationalProductsImages/mediumimages/Protein%20structure.jpg__

"Proteins." RCN D.C. Metro | High-Speed Internet, Digital Cable TV & Phone Service Provider. N.p., n.d. Web. 14 Apr. 2011. <http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/P/Proteins.html>.

Bailey, Regina. "Protein Function." Biology. N.p., n.d. Web. 14 Apr. 2011. <http://biology.about.com/od/molecularbiology/a/aa101904a.htm>.